Class: Linkage::Comparators::Within

Inherits:
Linkage::Comparator show all
Defined in:
lib/linkage/comparators/within.rb

Overview

Within is a integer comparator. It checks if two values are within a specified range. Score is either 0 to 1.

To use Within, you must specify one field for each record to use in the comparison, along with a range value.

Consider the following example, using a Linkage::Configuration as part of Dataset#link_with:

config.within(:foo, :bar, 5)

For each pair of records, if value of foo is within 5 (inclusive) of the value of bar, the score is 1. Otherwise, the score is 0.

Instance Attribute Summary

Attributes inherited from Linkage::Comparator

#weight

Instance Method Summary collapse

Methods inherited from Linkage::Comparator

klass_for, register, #score_and_notify, #score_dataset, #score_datasets, #type, #weigh

Constructor Details

#initialize(field_1, field_2, value) ⇒ Within

Returns a new instance of Within.



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# File 'lib/linkage/comparators/within.rb', line 19

def initialize(field_1, field_2, value)
  if field_1.ruby_type != field_2.ruby_type
    raise "fields must have the same type"
  end

  @name_1 = field_1.name
  @name_2 = field_2.name
  @value = value
end

Instance Method Details

#score(record_1, record_2) ⇒ Object 



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# File 'lib/linkage/comparators/within.rb', line 29

def score(record_1, record_2)
  (record_1[@name_1] - record_2[@name_2]).abs <= @value ? 1 : 0
end